Final answer:
Soil is approximately 50% air and water, with the rest comprising inorganic mineral matter and organic matter, both essential for supporting plant life and soil microorganisms.
Step-by-step explanation:
Generally speaking, soil is approximately 50% air plus water. Soil composition is crucial for plant growth and includes various components, such as inorganic mineral matter, organic matter, water, and air. In healthy soil, about 40 to 45 percent of the volume is made up of inorganic mineral matter, around 5 percent is organic matter, and the remaining 50 percent is a mix of water and air, with the ideal distribution having equal parts of both. Soil serves multiple functions including providing nutrients through the organic matter, serving as a water source for plants, and offering space for air which is needed for microorganisms and roots to breathe.